Givens Rotation: Find J(2,3) and Prove Orthogonality

[squenshl]

Homework Statement

A Givens rotation is a matrix J(i,k) that is the identity matrix except j_ii = j_kk = c and j_ik = -j_ki = s where c² + s² = 1. Let x = [1,-1,3]^T. Find the rotation matrix J(2,3) such that the third element of Jx is zero. Show that J(2,3) is orthogonal.

Homework Equations

To prove orthogonality just show J^TJ = I

The Attempt at a Solution

 

[SammyS]

What have you tried?

Where are you stuck?

 

[squenshl]

What does it mean when you have to find J(2,3)? Does it mean a 2 x 3 matrix?

 

[squenshl]

Never mind I think I got it